[RFC PATCH v1 0/5] Add support for O_MAYEXEC

[Jordan Glover]

On Wednesday, December 12, 2018 9:17 AM, Mickaël Salaün <mic at digikod.net> wrote:

> Hi,
>
> The goal of this patch series is to control script interpretation. A
> new O_MAYEXEC flag used by sys_open() is added to enable userland script
> interpreter to delegate to the kernel (and thus the system security
> policy) the permission to interpret scripts or other files containing
> what can be seen as commands.
>
> The security policy is the responsibility of an LSM. A basic
> system-wide policy is implemented with Yama and configurable through a
> sysctl.
>
> The initial idea come from CLIP OS and the original implementation has
> been used for more than 10 years:
> https://github.com/clipos-archive/clipos4_doc
>
> An introduction to O_MAYEXEC was given at the Linux Security Summit
> Europe 2018 - Linux Kernel Security Contributions by ANSSI:
> https://www.youtube.com/watch?v=chNjCRtPKQY&t=17m15s
> The "write xor execute" principle was explained at Kernel Recipes 2018 -
> CLIP OS: a defense-in-depth OS:
> https://www.youtube.com/watch?v=PjRE0uBtkHU&t=11m14s
>
> This patch series can be applied on top of v4.20-rc6. This can be
> tested with CONFIG_SECURITY_YAMA. I would really appreciate
> constructive comments on this RFC.
>
> Regards,
>

Are various interpreters upstreams interested in adding support
for O_MAYEXEC if it land in kernel? Did you contacted them about this?

Jordan